Counterfeit products are, unfortunately, widely available and often hard to spot. When counterfeiters produce fake goods, they typically copy the labeling, which may include a bar code or other type of mark, in addition to the actual products. At a superficial level, a counterfeited mark may appear genuine and even yield valid data when scanned (e.g., decode to the appropriate Universal Product Code). Many of the technologies currently available to counter such copying rely on the basic idea of visually comparing an image of a possible counterfeit mark with an image of an original mark.
A mark may be subjected to mechanical damage when the product on which the mark is located is handled, packed, shipped, etc. Damage may occur in some unknowable way, resulting in unpredictable changes to the mark. Typical forms of damage include scratches, ink runs, ink flaking off a surface, and dirt obscuring parts of the mark—any of which can distort the mark so that, even if the mark is genuine, it no longer resembles the original. As a result, the process conducting the comparison (e.g., image comparison software) may erroneously deem the mark being tested as counterfeit (a “false negative”).